Telephone repeater system



Jan, 6, 1931. H. H. ABBOTT ETAL `mLEPHoma REPEATER sYsTEu Filed Oct. 4,1929 4 ,Sheets-Sheet l y GQ ik xmm Jan.6; 1931. H. H. ABBOTT ETAL1,788,007

TELEPHONE REPEATER sYsTsl Filed oct. 4, 1929 4 sheets-Sheet. 2

HQE.

Jams, 1931.

Filed oct. 4, 1929 4. Sheets-Sheet. 3

n n Ur N -L BN m B f T Af r H5 A HF., QU .O m l Nw .V... W

VIII.

Patented Jan. 6, 1931 i i f i i the opaque SIGNOR CCO AMERICAN NEWYoun-AND SAID ENTZ k.s-sslefnoa To BELL TELEPHONE LABOBATQBIES. IN-

comonarnn, orenuwmomi, n.1., A'CORROBATIVON OENEW Yonai.v

i mELE2HoNE--REPEATER` sieren.

` 'Animation inea` october.11j, 19,29. Y seien.No.ae'aimvt e Thisinvention relates to# signal-ing;k lar-- rangements for longe," orghighly" attenuated? P. B. X.y tie-linesorinter-o c eVtrunkshavingltelephone `repeatersv or e other"fci`rcuits,

opaquejto direct current, included therein.

The object of lthe invention-f is. to increase the direct currentsignaling'rangeeflinesfofy this character. v

ik feature ofl theinventicn wherehyftlreabove object isfattained residesin 'an auxil-A laryl circuit including ar y p repeater channel connectedto the line around;k

circuits, whereby direct [current y signals' applied to the; line at`eitherjexchange are repeated andxpassed around the` opague:

circuits to control' respective' Y signal'r` devices' at the otherexchange.

The invention will nofivllie descriledivviths.

the aid of the accompanyingdrawings: e

VFigs. vl and 2 ofthe a ticdine circuit; extending between-itwowidelyseparated privatebranchexchanges, which circuitinclu'des certainintermediate equipterminating circuit ment, Fig. 1y showingv a Y K forJoining a tWo-Wireftoaffour1vv1re linea-nd another terminati-ngcircuitiv for `joining a four-Wire line to af second two-Wire line` and'2 `shows a two-Wiretelephone repeater b ass arran'dementinaccordance'with.

the present .invention which adapted," to

translate direct* current calling1 and rsupervvisory signals,originating at "Figs, 3 and' 4f when j placed togetherwith j F 14' atthe! right, represent 1a'` tieline circuit extending [between ment,comprising a terminating circuit for joining tWovWire line toa four-Wireline,rg ak four-'Wire*repeaterv and composite circuitl e e u r d' neland a-.telegraph nnpul'sei'ncomingover apparatus thereingjas/shown inFig, van

. ment similu;` to Figs. kdirect current `sigrnils' aroundthe repeaterstwo-Waytelegraplrl drawing' W lienplacediv together, with Fig. 2`atthe'right, represent:

either B. X.,

into :standard telegraph impulses andto y transmit them, overanyvavailable'telegraph..not operate 'at'thls time. Y

closes, at its upper @We 1 Widely* Separated P'.Y B XFS', which includesintermediateequip v vit being suilicienttoj's other-compositecircuitapparatus andA` a ter--l minating circuit `rfor joining-tha lastnamed directly to anothentwo-Wire line; as shownin Fig-f4. Y

TheseJ7 figures (#3 and QjshoWl anvr arrange- `1I andx 21 yforIcy-passing and terminating circuits', in lwhichethe'VL telegraph;channel ier-superimposed ony one'o" the telephone..lines'.` Fig.' 8!al'soshows arr-arrangement for bypassing direct current signals,` aroundtheterminating 'circuit' which- -jcins'the two-Wirewithithefour-wireline. e

.Considering the arrangement shown 'by Flers.Y 'Land 2, We Willassumethe operator at' with BB. (Fig) over thearrangement shown-)1 ofthetieline TD1, "whereupon battery flows kout `'overrthe tip andringconductors of the tie-line TLln the well known ervisory lamp isGonducters Vl manner. f The cal-lingY sup lighted' at this" time as'usual.

` and'A 2 are: bridgedacross theftie-line TLllr and serve te'ccnnecttlie;bypass- 'circuit tothe; tie-line andv therefore line- TLl Howsthrough the retard coil' 3, back contacts 4l and@ 5 of relay,liifghresistance 7 r and; the liighfresistance upper and low resstancelower windings of rela-518, where-V uporrrelai;Tv 8 lis'energizked andcloses its eontactsto-'energize rel'ay9in anil obvious circuit; Due,tothe highrresistance values of resistance 7 and the upper windings of2 relay 8 the y 1 Newman, N. Y.; sainemaom'nfes# u i TELEPHONEsa/NnTELEGRAPHQQMBANY, .A coRnoRNmoNfoE.

currentl from the 'Ati'e- PIB. X 'epeirators ycordV supervisoryfrelaydoee Y,

' Relay 9i in? operating contacts, thesending loop repeaterkfTRl' whichcauses S1 oftthe ytelegraph the repeater t graph channel.

Repeate-rs T-Rl', TR2; *TRB "andi are standardV telegraph, repeaterswelll 'knowniintheart'and' 'a vdescription ofi their circuit arerangements and operation isnot necessary;

Atate ythat a closureofthe sending yloop Si? causes QtelegraphgfimpulseY tobetransmittedouti overfthe'ftelegraphehan Y the supervisoryylainp atthiswtiiiie. Opera Relay 12 the telegraph channel causes a correspondingimpulse of direct current to be connected to the; receiving loop R1.

When relay y9 was energized ital'so opened l its contacts 10 fand closedits; contacts` A 1-1, thereby connecting the receiving loop R1 oi'thetelegraph repeater to relay 12, vvliich're` layfis thereupon incondition tofbeoperated whenthe operator at the distantfP'. B. X12.

answers the call. i

Y Returning to the transmission .of the tele.-V

graph impulse from repeater TR1, whenthis impulse is received atrepeaterTR2' (Fig.2) fit causes battery and ground tobe connected to thereceiving loop R2, which Vcauses the operationwoffrelay 13 ina circuitwhich Yin- .dudesv the i .upper .back AContacts -pf relay 14.-.

Relayal infoperating,'connectsat its innenv contacts battery'andgroundjt'o thetie-line 'PL2 and thenceto B. X. 2 which .en ergiaesa,lirie relay `(not shown) to display asigiial before the operatortovindicate the call.

Relay 16,.'which is when lthe. operator answering supervisory Y,relayyoft-he cordwcircuit now operates and, prevents` lighting ot tion ofrelaylicompletes an yobviousV circuit to operate, relay 1'( iwhichopens,at its upper contacts, normal short-circuits acrossrthe.

repeater side ofthe transformers 1 5. and-.18',

thereby conditioning that yend of "the teleV phone circuit for talking.

Gperation offrelay 1T `also closes., its lower contacts, thesendingrloop S2 ofltele- .graph repeaterv TR2, which causes ai telegraphimpulse to be sent yback over thetele channel toward 1, which' is .Y

TR1, -gvvhichA sends a `,corresponding impulse. offdirect cur--g rent'overthe 'receivingY loopjRl and .contacts 11 of ,operatedrrelay 9'toYenergize relay'12.. .1in operating'connects lthe tieline graph yreceived by `telegrapli repeater through to the-terminating circuit19,,closes Yto theV circuit of -the compromiseV network-.2O itslowerniost contacts, 4shunt-s .high resistancefand the upper, or highresistance, windingo relay 8, thereby lowering the` bridge resistanceacross TLl vto causejtli'esuper-visory ,relay `in the and, -at

release.; .Relay 13. inV releasing diesen- Y 1 of thesupervisoryrelayofthe cord circuit n 2 andtheQcoiisequent.lightingfovthe supervisory' lamp .to indicatetothe Aopera-, V

at P. B.

in theY battery circuit just referred to, is Qinarginal.andwdoes notoperate in series with theline; relay bridged s acrossdTLh2. However,

answers, the Ybridged .resistance is decreased suiiciently to. causerelay 16st@ operate. The

. @ede-l0' 0f [relay p Vtelry andgroiindto .theI tie line TLl, throughoperators cord .circuit Y I X. 1 to operate, thereby ejatinguishingthecallingV supervisory lamp-which was, lighted when the operatorplugged linto the .YP vfline; to initiate the call.'l

"operator-;disconn'ects, relays. 8, 9, 12,v and 17 'f nectsbattery -feedrelay V16 from its-bridged,y A association Awith This causes'release torat P. B. X. 2 that thel operator at P. B. X.Y l has disconnected. Relayv17, when released, applies short circuits to the repeater side oftransformers 15 and 18, thereby disabling the talking circuit. f l

' In case the calling operator should imine'diately replug line TLl,before the operator at P; B. .X42 has impulse which would cause relay 13to operate *againconnect battery and ground to thetie line TL2 toV againextinguish the fsupeivisorylamp of the cord circuit at P.

disconnected, relays 8 'andi 9fwould 'reope'rate to send anothertelegraph TL2rwrhicrh lights the supervisory lamp. at hei-(position andVconnectsA battery and .ground to TL2vwhichy operates relay 21,

which in, turn operates relay 14 This relay closes at its lower contactssending loop S2 otfthegrepeater TR2which causes repeater TR1 to .connectbattery to there- ,ceiving loop .Rl toopferaterelay V6 over con- Relay 6connects batthegwindings of vmarginal relay 22, to light hanne lampY apryB X.

closes an ebyious circuit for. relay 23, which closes the"`vlcoinproiiriise network circuit l20, connects; the tie line. TL1 ,toAvthe terminating circiuit19, and atiits inner lower contactsclosesthesendin loop S1 yof the telegraph repeater..T-Rl, wich transmitsa telegraph impulsepyer theltelegraph channel to re- .peaterjl'R2Q where.battery is connected `to receiving loopR2 to operate relay 24,A in acircuit includingcontact V25 vof relay 14, which is operated at this.tirne.. Relay 2 4 in VoperatinguV shortcircuits lhe lower i( highresistance) windinguof relay 2 thereby decreasing the .brdeelesistenceacross TLQY-Suently t0 cause j operation ofthe:- supervisory relay .Y at

B. X. 2, and the consequent darkening of, the cordv I"supervisoryv lampwhich indicates p Y l. Relay 22 being marginal does not operate untilthe called operator answers, at which time, however, it Y lli)thattlie.calledoperatorlias answered.` Relay n Mingperafti-ng alsoremoves the, vnormal short circuits roinj `tliefrepeater, side. ofthe;trans- Y forine'rsil and. 18. ,Y .Disconnection by 4the Yoperator 2releases relay 2 1 Vwhich in: turn, releases `relay VV14.- to..open thesend- 'l'lhisreleases relay @which disire-1.091@ $12.

compromise network 20, and V'also disconnects the line TLl from theterminatingcircuit19.@ Release of relay 23 also opens the sending'y olightsyas usual, andrelay4l operates thereby loop Sl to repeater Fromthe foregoing in either direction in the usual manner, these` signalsbeing repeated and transmitted, by

.. yineansof a telegraph repeater system, around 'the intermediateequipment without aifectin'g it or'being affected thereby.

The tie line circuit connecting P. B. 'X'.

with P. B. X. 4 (Figs. 3 and`4) is made upof is connected to therfour-wire 'line through-a terminating circuit 30 shown Within'fthejlbroken line rectangle L0L. A four-Wire f repeater31-is insertedbetweenthe terminals of the four-Wire line, and a our-wire terminating circuit32 serves to connect the fourl connects battery andground tothereceiving.- `loop R4 which causes 'thefoperation of relay wire line tothe two-wire line TL4.

In the present caseV the telegraph repeater perfectly obvious from'aninspection of the drawing. 4 Y f` Theintermediate four-wire telephone'repeater, and the telegraph repeaterfTR3' to;v Vgether with itsvassociated equipment,l are` shown enclosed Within a second broken line'yI); l o f telegraph'impulse to ybe sen-t backove-r the telegraph channelto repeater 'TR3-*which The other endfof the-/fou'r-wire circuit is2joined to the two-wire line TL4 at which telegraph yrepeater o ireceiving loop R3 `which Vin turn operates repointthe other end of thechannel is located. 1 Y

The telegraph" repeater channelin this in-ff' stance is a compositecircuit formedbyf the "f two conductors of one side of thefourwire Theoperation ofthe telegraph repeater by-p'ass arrangement, as shown inFigs. 3 and 4, is substantially the same as previously described.

When the operator at P.' B. 3 plugs into TL3 battery from the ringconductor of TLS flows over lead 33 through theyreta'rdation coil 34'toVthe mid-point of theright-hand winding of transformer 35, over the twocon-- ductors of the lower pair of wires'in parallel teV the mid-pointofthe left-hand winding of repeating coil 36, thence over conductor 37,contacts 38 of relay 39, high resistance 40,

v"cothwindings of relay 4l in series, contacts description, it lwill beunderstood that the l?. B. X. operators signal 42' Greeley 39,Conductora to the .midpointof the--left-/hand winding of- `transformer44 and thencefin .parallel over both conductorsv of theupperiside 'ofthe fourwirej line. tothe mid-point kof the right-hand winding oi'transformer 45. F rom this point thecircuit passesover conductor 46 andretardation coil 341 to lgroundsonf the tip conductor of TL3.v

`.T.hef operators cord'v supervisory Alamp completing an obvious circuitto operate re-4 layf47zf Due to-thexhighvalues of resistance 'zov 401an'dL :the-lower windingof lrelay 4l the supervisory'relay intheoperators cord cir` cuit-'(not shown) doesnotV operate at this time.

'. `Relay 47vin' operating closes, at its lower contacta-the :sendingloop S3 of thetelee phone .repeater TR3 which causes the repeater toY.send-a' telegraph impulse over the telerv graph channelgincluding bothconductorsfof one-halt ofl the"fourwirecircuit; Y JRela-y!` '47, inoperating, .alsofV connects the receivingloopR3 to relayf48therebyconditioningV that relay for operationwhen the operator atyPpB. X. 4answers.v

The'telegraph impulse following operation of relay 47 is receivedbyrepeater TR4 which 494119 'Circuit-Which includes contacts 50 otrelaylp'f 'Relay-49, in operatingl connects battery andiground,throug`hthe windings of relay 52,"

thetie line TL4.` Thislcauses the usual line signal to be lighted beforethe operator. Relay52` is marginal and doesnotoperate until the operatoranswers, atwhich time it completes lla' circuit for operating relay53which clo'se's' the circuit 'of network 54, connects theterminatingcircuit32 to the` tie line`TL4`and,

at itsupp'erin'ner contacts', closes the sending loop S4 `of theVrepeater TR4 which Vcauses a translates it into a direct current impulseover lay48. 'Relayl 48-opens, at its upper and low'ermosty 1 contacts,-normal short-circuits across' the input y'circuits ofA the four-wirerely peater 3l, thereby "conditionin'or the repeater for talking, yandcloses atits inner lower con- "When thecallingoperator disconnects,`rfe"l lays 41, 47, 48,' 49', 52"and `53 release. Relay` 49 disconnectsbattery andl ground from they tieline TL4- which causes release of thecord and extinguish-tha l supervisory relay and the consequent lighting'ofthe supervisory lamp at P; B. X. 4. Relay 53,kv released, Iopens thecircuit of network 20,

disconnects TLftfromtheztefmiDtngcrnutf.

32and opensthe sendingfloop Sft-,whiclicauses relay 49'- whichv againconnects; ,fbattery and ditionfroln the repeater-31.-

ground to the tie; line Tl'iftozagainxextnf.; fruish j the supervisory'lamp at 1P; .BLQ- i Y velay- 52 -will reoperate inthis .cincnitaandfcauserelay 53 to operateitoagainconditionY Vthe, -circuit for talking.;Relay f.'53-fcauawsit8- toV operate which removes the disabling con-frelay 54 which operates relay-151 which:semis:` p an'. impulsejto. the;other; end :of thefte-legzl'aphn -hannelgito :operate .relay 59; Relay39e-icone.; nects battery 'and .ground 'to' conductors I and 43 inseriesfwithadouble'fwound:relayiL When theoperatorfatfl?. B.X..31Lanswers,

relay 55' operates which completes@ circuitxto energize relay :5 6lwhich 'removesftheinorrmal Y short-circuit acrossfthesinputiofirepeaterand `closesrtlie; sending :loopdl S3; -Whichfcauses an impulse `t0'-be.`transmitted- :to IR4 iwhich in turncausesfrelayf57zto!operate.jf'llhisicloses the:networkzcircuitlaanidrconnectsftheltermif; 1 natingcircuit 82 atofftlie' line TD4; Relay 57,- in operating also shunts ,theresistance, 'and-i the upper (highresistancei), 1windingiof relay 54.Thiscauses thewsuperni'soryflamp 1:12.; f a Bra-..4 to "beextinguished-.l1 A Y l W hat isclai'med is:

with a line extendingfbetweentwoexohaitges and*` having circuitarrangementsincluded v thereinwhich are#substantially-.opaque-toldierect current,l .ofanauxiliary r-ciircuitf :for :ref

laying f direct Y `current line f and f :supereuisoiy 2 signals around:said 'opaqnev \c1rcn 1ts;aniboth; directions, said :auxiliaryoircuitquncluding two twolway telegraph`v` repeaters intemilfbY neotedby agtelegrraph-channeh p. y 2. VInga Vtelephone system, A`incombination Vwitlra'line extending-.between twofexcharxges Jand.;-liayingdg`v circuit arrangements g-substam, tially opaqueto directcurrent includedther'e.-`

' our names this in, an auxiliary 'circuit ionrrelayingdirect currentline and supervisory Vsignals,around g said kop aque circuits iin bothadireetionsrrsaid auxiliary `circuit comprising1-lftwor1 two=way fr 1telegraph repeaterseinterconnected#aya d;e1e graph channel, roneofVsaidl.repeatersbeing,A associated with -Saidj linethrouglli-'leyfmelS-f intermediate thelopaque circnitslandfnnefexfschange and the other repeat-3er: with; the line fthrougl'ir'elaymeansiintermediatetheeopaquei p Y circuits zand-theotherexchange.VV p

lil*iefextreriding4v j between two exch anges .fha-ning @its terminalsarranged-fior direct Current signaling-inlbethz, l v directions `:andincluding- Y :o111c u1t =,Y .armangeef insegner mentsf'snbstantially opaque to direct current; an ,auxiliary circuit-including :two two-waytelegzmph vrepeaters and a-n 'i terconnectingtelegraphfrchanneltherefonand means, associatingsaid line and fiepeaters toAcause direct currentesignals -applied'to saidV lineat one exohangeftobeitranslated into telegraph sit; nals `byzone frepeatenand` transmittedover said l channel, :received a and 'retranslated into direct currentsignals by the-other repeater to 1 actuate the signaling apparatus atvthe otherexcha'nge. f

Ineatelephonefstgnaling system', two ex- Changes, av-linelinterconnecting them having interposed circuit arrangementssubstan- Atially aopaque to :dire'ct -f.curr ent,4 a direct \currentsignaling deviceassociated with said linevpat each exchangeyanoperatorslink cin cuit. at cache-Xchange adaptedY to be Iconnectf.ved-Ato,-saielfline, asource of? direct currentat eachexchangeifadapted,tohe connectedto said line irunderfnontrol' of yits lrespective ylinlcircuitca circuit including 'a plurality.- ofV tele-Y graphirepeaters,one end offsaidcircuit being. connecte-,dato said line between oneexchange and thee Aopaque circuits, Land the other vend betweenAVthe-opaque ,circuits andthe other exchangey and meansV in saide'circuit :between said line and said repeaters to -cause :directcurrentrappliedtothe line. at either exchange tolbe translatedintotelegraphfsignalsby one repeater-.and transmittedto a secondfrepeater,

andfother means betweensaid line and :said

repeaters responsive' to the-reception gof telegraph-xslgnals Yloyfe1the'r repeater to connect p j directfcunrent Yto said linejtooperate -one of l. In La 4telephonesystem,` combinationsaidasignalideyices.

.5.V V'In .a :telephonesignalingjsystenn.,.two i exchanges, a lineextending therebetweenvim cludlng f c1rcn1t arrangements substantially Yopaque ito direct \cunr'ents, means at Veach vof said exchangesfontransmitting toand re-l ceiving :Eromsaadline direct' current llineand supervisory.A signal ',impulses, and means -including telegraph.repeaters zand ran intercon` nectingstelegijaph@cliann-eljthereitor tolrelay Y said direct' current signals around said opaqueecircuitAarrangenients inA bot-h fdirections.-Vv f v g Vi .Y

' .In witnesswhereot, we yhereunto.subscribe lst day of October, 1929.

" IEERDINAND S.. .ENTZ

